Last week saw the London premiere of your new movie Anchorman 2. Was it a big night on the Ron Burgundy "Great Odin's Raven" whisky?Not for me. A few nights ago we did a meet and greet with fans in a pub in Dublin, an hour and a half before the premiere, and that was interesting because we were being plied with the freshest Guinness available. That turned out to be one of the more enjoyable promotions I've ever attended. But everywhere we've gone so far, there seems to be a party atmosphere. I read that people are going to get dressed up as the characters and go to midnight screenings – like a Rocky Horror Picture Show.

What's your favourite line in the new film?Paul Rudd has a line where he says: "You've heard the old saying, 'Nope'?" It's just his delivery that sells it. He's stealthily funny.

There's a video doing the rounds of your audition for the original Anchorman 10 years ago. How important was that?Oh, huge. Adam [McKay, the director] and Will [Ferrell] are probably more responsible for my subsequent career than anybody, because they gave me a shot. I wasn't well known – none of us were except Paul – but they took a chance and from there I met Judd Apatow, one of the producers, and we wrote The 40-Year-Old Virgin together. That led to other things, so it was an incredibly important time in my career.

In Anchorman 2 your character Brick Tamland eats lipstick and butter. Where would you draw the line for a laugh?Those were moulding chocolate – I wasn't getting stunt pay for those days – but I don't think you draw many lines in comedy. Look at people like Will, who will always go out on a limb comedically and take all sorts of chances. In this movie there was one day where they were scooping jellyfish out of the way with a shovel so he could swim in the ocean. He'll try anything: he doesn't put any constraints on how he approaches comedy.

There are a record-breaking number of cameos in this film, from Harrison Ford to Kanye West. Did that get surreal?It was surreal, and it felt like camp, comedy camp: it was all for the sake of being silly for a few days and sharing in that. You know, it's a movie that's not trying to change the world. On a certain level it is smart and insightful but overall it's just a big, fun, ridiculous movie. I hope people take to that because it's refreshing to go to something that's only agenda is to make people laugh.

You've just appeared on Saturday Night Live in the US with One Direction. Are you a fan?My daughter's a big fan. I got a signed photo of them and that's going to be in the Christmas stocking. They were so sweet. I can't imagine how tough it is to be that age, that successful, that in-demand and still remain grounded and cool and human. And they are.

A lot of celebrities have mansions and garages full of Ferraris. But you're the only one, to my knowledge, who has bought a general store in Massachusetts…Yeah, it's a little shop that my sister-in-law runs. I had no intention of owning a general store but I grew up in Massachusetts with one of those stores close to my home and it has since disappeared, and I just thought, "That was special to me as a child, I'd love to preserve this for other people." People text one another but I think there's a lack of the face-to-face conversation – the local barbershop, the local diner, the place where people congregate – and this is one of those places. You sit on the front porch eating a popsicle in the summertime with your kids. It's very comforting to me. It's just from a simpler time.

Do you have mixed feelings about technology? You seem to post on Twitter about once a month…I don't even know why I went on, because I don't find my life so interesting that I think people want to share in my daily thoughts. But some people are hilarious.

I know you're an admirer of Peter Sellers. Did you hear this week that they retrieved a couple of his early short films from a skip?Oh, I hadn't, but I'm a huge fan. I'm interested to see.

What is it you like about Sellers?He never indicated that he thought what he was doing was funny; he never winked at the camera. He was always completely committed to the characters he played. What I learned from watching him was that characters in comedies don't know they are in a comedy. They are just in life. He was a perfect personification of that.

You've written scripts in the past – a couple of episodes of the US version of The Office, The 40-Year-Old Virgin – but not for a while. Will you go back to that?I've actually written a very silly TV pilot with my wife [Nancy, also an actor] called Tribeca. It's essentially a comedic version of Law and Order with a female protagonist and it's completely silly. There's no sentiment at all; it's sort of in the vein of Naked Gun and Police Squad. I'm going to direct the pilot episode in February, so we are casting right now. It's a hard thing to find the right actors who will play it straight; again, not indicating that they are doing anything funny but at the same time doing the most ridiculous things.

It is true there's an alternate version of Anchorman 2 out there?Yes, Adam has a cut of the movie that has all different jokes; I think it will be on the DVD. It's all the same scenes but – because they had many options for every scene – every joke in the movie is switched out for a different option or an improvised scene. There was an entire musical number, complete with background dancers, high production values that didn't end up in the final cut. We spent a whole week shooting it and I wouldn't go as far as to say it's Busby Berkeley-esque, but it was a pretty big production. But that's what's great about Adam and Will: they set a liberating tone, and people are willing to take more chances. They create this freedom to fail. And if it's terrible they're just not going to put it in the movie.